Abstract:Objective:To elucidate the mechanisms of disruption of intestinal mucosa barrier in obstructive jaundice.
Methods :The obstructive jaundice model of rats was set up.At 10 d and 20 d after operation,immunohistochemistry and Western-blot techniques were used to examine the distribution and expression of tight junction proteins (ZO-1,Occludin) and myosin light chain kinase（MLCK）in intestinal mucosa.
Results:In normal control groups, the staining of ZO-1 and occludin was predominantly localized to the margins of the epithelial cells and the apex of the cell membrane, and displayed a continuous and uniform distribution along the under surface of the villae. MLCK was distributed mainly in cytoplasm.In obstructive jaundice groups, ZO-1 and occludin staining appeared discontinuous and vague,with rough edges and spiculate processes.The staining of MLCK was also discontinuous and scanty.The strong positive express ratio of ZO-1,Occludin and MLCK were obviously lower in two experiment group than those in the control group all P＜0.05). ZO-1 was significantly decreased in 20 d group than that in 10 d group（14.3 % vs28.6 %，P＜0.05), but no significant difference in occludin and MLCK staining between 10 d group and 20 d group.Similar outcomes were obtained by quantitative analysis of Western blot images.
Conclusions:Obstructive jaundice rats have distribution of ZO-1,occludin and MLCK in ileum mucous membrane epithelium, and is associated with breakdown of the integrity of the intestinal barrier.